modify tweets list, adjust 2 login buttons

1. change the time for tweets to be correct.
2. change the font of the tweets to the same with font size for article
content.
3. When click "hot","analysis".. just to Analysis section automatically.
4. change loadMore style of loading tweets to be that the system will
collect tweets every 20secs. It then shows how many new tweets. When
users click the button, the new tweets will be loaded to view.
5. reduce the window scroll bar.
6. manage to let the tweet list width automatically fit the dimension
change.